From 2046b141cfd29de290c398fa5b31a8607e19d517 Mon Sep 17 00:00:00 2001
From: dkeysil <me@dkeysil.com>
Date: Mon, 26 Aug 2024 16:28:29 +0200
Subject: [PATCH] Add get transaction count method to eth client

---
 ethereum/client.go            | 44 ++++++++++++++++++++++++++++-------
 ethereum/mocks/mock_client.go | 15 ++++++++++++
 2 files changed, 51 insertions(+), 8 deletions(-)

diff --git a/ethereum/client.go b/ethereum/client.go
index b31d9ab..c3e15eb 100644
--- a/ethereum/client.go
+++ b/ethereum/client.go
@@ -62,6 +62,7 @@ type Client interface {
 	BlockNumber(ctx context.Context) (*big.Int, error)
 	TransactionReceipt(ctx context.Context, txHash string) (*domain.TransactionReceipt, error)
 	ChainID(ctx context.Context) (*big.Int, error)
+	GetTransactionCount(ctx context.Context, address string, blockNumber *big.Int) (*big.Int, error)
 	TraceBlock(ctx context.Context, number *big.Int) ([]domain.Trace, error)
 	DebugTraceCall(
 		ctx context.Context, req *domain.TraceCallTransaction,
@@ -75,14 +76,15 @@ type Client interface {
 }
 
 const (
-	blocksByNumber     = "eth_getBlockByNumber"
-	blocksByHash       = "eth_getBlockByHash"
-	blockNumber        = "eth_blockNumber"
-	getLogs            = "eth_getLogs"
-	transactionReceipt = "eth_getTransactionReceipt"
-	traceBlock         = "trace_block"
-	debugTraceCall     = "debug_traceCall"
-	chainId            = "eth_chainId"
+	blocksByNumber      = "eth_getBlockByNumber"
+	blocksByHash        = "eth_getBlockByHash"
+	blockNumber         = "eth_blockNumber"
+	getLogs             = "eth_getLogs"
+	transactionReceipt  = "eth_getTransactionReceipt"
+	traceBlock          = "trace_block"
+	debugTraceCall      = "debug_traceCall"
+	chainId             = "eth_chainId"
+	getTransactionCount = "eth_getTransactionCount"
 )
 
 const defaultRetryInterval = time.Second * 15
@@ -384,6 +386,32 @@ func (e *streamEthClient) TransactionReceipt(ctx context.Context, txHash string)
 	return &result, err
 }
 
+// GetTransactionCount returns the transaction count for an address
+func (e *streamEthClient) GetTransactionCount(ctx context.Context, address string, blockNumber *big.Int) (*big.Int, error) {
+	name := fmt.Sprintf("%s(%s, %s)", getTransactionCount, address, blockNumber)
+	log.Debugf(name)
+	var result string
+	err := withBackoff(ctx, name, func(ctx context.Context) error {
+		err := e.rpcClient.CallContext(ctx, &result, getTransactionCount, address, blockNumber)
+		if err != nil {
+			return err
+		}
+		if result == "" {
+			return ErrNotFound
+		}
+		return nil
+	}, RetryOptions{
+		MinBackoff:     pointDur(e.retryInterval),
+		MaxElapsedTime: pointDur(12 * time.Hour),
+		MaxBackoff:     pointDur(e.retryInterval),
+	}, nil, nil)
+	if err != nil {
+		return nil, err
+	}
+
+	return utils.HexToBigInt(result)
+}
+
 // SubscribeToHead subscribes to the blockchain head and returns a channel which provides
 // the latest block headers. The channel is closed when subscription encounters an error
 // or becomes inactive (e.g. due to a hanging connection).
diff --git a/ethereum/mocks/mock_client.go b/ethereum/mocks/mock_client.go
index 54255c8..3a33480 100644
--- a/ethereum/mocks/mock_client.go
+++ b/ethereum/mocks/mock_client.go
@@ -599,6 +599,21 @@ func (mr *MockClientMockRecorder) GetLogs(ctx, q interface{}) *gomock.Call {
 	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "GetLogs", reflect.TypeOf((*MockClient)(nil).GetLogs), ctx, q)
 }
 
+// GetTransactionCount mocks base method.
+func (m *MockClient) GetTransactionCount(ctx context.Context, address string, blockNumber *big.Int) (*big.Int, error) {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "GetTransactionCount", ctx, address, blockNumber)
+	ret0, _ := ret[0].(*big.Int)
+	ret1, _ := ret[1].(error)
+	return ret0, ret1
+}
+
+// GetTransactionCount indicates an expected call of GetTransactionCount.
+func (mr *MockClientMockRecorder) GetTransactionCount(ctx, address, blockNumber interface{}) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "GetTransactionCount", reflect.TypeOf((*MockClient)(nil).GetTransactionCount), ctx, address, blockNumber)
+}
+
 // Health mocks base method.
 func (m *MockClient) Health() health.Reports {
 	m.ctrl.T.Helper()